68 research outputs found
Single electron relativistic clock interferometer
Although time is one of the fundamental notions in physics, it does not have
a unique description. In quantum theory time is a parameter ordering the
succession of the probability amplitudes of a quantum system, while according
to relativity theory each system experiences in general a different proper
time, depending on the system's world line, due to time to time dilation. It is
therefore of fundamental interest to test the notion of time in the regime
where both quantum and relativistic effects play a role, for example, when
different amplitudes of a single quantum clock experience different magnitudes
of time dilation. Here we propose a realization of such an experiment with a
single electron in a Penning trap. The clock can be implemented in the
electronic spin precession and its time dilation then depends on the radial
(cyclotron) state of the electron. We show that coherent manipulation and
detection of the electron can be achieved already with present day technology.
A single electron in a Penning trap is a technologically ready platform where
the notion of time can be probed in a hitherto untested regime, where it
requires a relativistic as well as quantum description.Comment: 9 pages, 4 figure
Ensuring ecological and technogenic safety of Ukrainian transport complex
У статті розглядаються питання забезпечення екологічної та техногегнної безпеки транспортного комплексу України. Визначені напрямки дій, спрямованих на покращення екологічної та техногенної безпеки транспортного комплексу
Trace elements in soils of oases of Enderby Land (on an example of Vecherny oasis)
The content of trace elements in the soils of the Vecherny Oasis (Enderby Land, East Antarctica), where the construction of the Belarusian Antarctic Station started in December 2015, is considered. The results of the research are based on data collected during four Belarusian Antarctic expeditions in the period from 2011 to 2017, and analytical testing of soil samples taken from impacted and non-impacted sites. A total of 22 soil samples were analyzed for the content of trace elements; to compare the levels of accumulation and possible migration pathways, 7 samples of bottom sediments were also analyzed. Determination of trace elements was carried out using the AAS method (Cd, Cr, Cu, Pb, Ni, Zn, Fe, Mn) and emission spectral analysis (about 40 elements). The average values and range of concentrations of trace elements in soils and bottom sediments of the oasis are presented. The possible dependence of the trace elements content on the location positions in the landscape and on the sources of impact is discussed. It is shown, that the variability of metals content in soil profile for background site is low. In comparison with other oases of Antarctica no hotspots have been revealed and no significant areas of soil contamination have been identified yet, which is largely due to the fragmentation of the soil cover and lack of significant sources of pollution
Readiness of the marine personnel in Ukrainе to join the Manila amendments to the Convention and STCW Code
В статті розглядаються питання можливості працевлаштування морських кадрів України у звя`зку з прийняттям Манільских поправок к Конвенції та Кодексу ПДНВ
FOCUSED ION BEAM IMPLANTATION OF Er-IONS IN NON-CONDUCTING SOLIDS
The implantation of single Er-ions in dielectrics is a very promising tool for the creation of future quantum information
processing devices. In the following, the influence of surface charges on the focused ion beam is investigated. Different fluences
were used and the current on the sample during implantation was measured. As not definite results were obtained, further
methods will be provided
Optical vector network analysis of ultra-narrow transitions in Er:LiYF
We present optical vector network analysis (OVNA) of an isotopically purified
Er:LiYF crystal. The OVNA method is based on generation
and detection of modulated optical sideband by using a radio-frequency vector
network analyzer. This technique is widely used in the field of microwave
photonics for the characterization of optical responses of optical devices such
as filters and high-Q resonators. However, dense solid-state atomic ensembles
induce a large phase shift on one of the optical sidebands which results in the
appearance of extra features on the measured transmission response. We present
a simple theoretical model which accurately describes the observed spectra and
helps to reconstruct the absorption profile of a solid-state atomic ensemble as
well as corresponding change of the refractive index in the vicinity of atomic
resonances.Comment: 4 pages, 5 figure
Inventory of unintentional POPs emission from anthropogenic sources in Antarctica
In spite of remote location and very limited human activities, Antarctica is affected by persistent organic pollutants (POPs). POPs investigation in Antarctica has a comparatively long history, but there are still large knowledge gaps in assessment of their emission into environment. In the paper the results of the first inventory of unintentional POPs emission from anthropogenic sources in Antarctica for modern period and preliminary estimate for the late 1980s are presented. Assessment of dioxin/furans (PCDD/Fs) emission in different media, as well as polychlorinated biphenyls (PCBs) and hexachlorobenzene (HCB) in air is based on methodology of emission factors and indicators of human activity. The following sources of POPs emission have been estimated: power generation and heating, waste incineration, mobile sources and open burning of waste (in the past). According to the data obtained, annual PCDD/Fs air emission for modern period comprises 60.74 mg toxic equivalent (TEQ), PCBs – 5.09 mg TEQ, and HCB – 457.6 mg. Additionally 2.5 mg TEQ of dioxin/furans is released to residues, so total PCDD/Fs emission is amounted 63.23 mg TEQ. Waste incineration makes the greatest contribution to POPs emission (96% of PCDD/Fs, 98% of PCBs and 36% of HCB air emission). In late 1980s open burning of waste was the major source of POPs. Retrospective assessment shows that over a 30-year period air emissions of PCDD/Fs decreased about 13 times, PCBs—15 times and HCB—57 times, primarily due to the prohibition of open burning of waste in compliance with the Protocol on Environmental Protection to the Antarctic Treaty requirements
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